Modder Francois Dion created the Raspberry-Pi-a-Sketch with a little help from Python after attending a session at PyPTUG (the PYthon Piedmont Triad User Group) about motors.
“We did a lot of stuff with motors. DC, servos, H bridges, PWM and steppers,” Dion explained. “It was a very dense 3 hours. We covered a lot, and it was a lot of fun.”
Components? An Etch-a-Sketch, some stepper motors, a battery pack, a Pi, an 8-channel Darlington pair and some leds, wires and headers.
According to Liz at the Raspberry Pi Foundation, Dion has designed a device that uses Python to draw all those things on an Etch-a-Sketch that, as kids, “had us throwing the things at the floor in frustration” at the uselessness of our fat thumbs.
“Horizontal, vertical and diagonal lines? No problem. And with a bit of help from Bresenham’s algorithm, you can draw circles too,” Liz wrote in a blog post.
“This sort of demonstration is exactly the sort of thing that captures the imagination, and opens up the eyes to what you can achieve with a little programming and a little solder flux.”
Instructions on how to configure the Raspberry Pi-A-Sketch hardware are available at Raspberry Pi Python Adventures, while Dion plans to write a blog post about the Python software side of the Sketch. In the meantime, the source code can be downloaded here at Bitbucket.